KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
5.3 | - |
2-nitrophenyl beta-D-galactoside | release of 2-nitrophenol, pH 7.5, 80°C | Pyrococcus furiosus | |
186 | - |
lactose | release of D-glucose, pH 7.5, 80°C | Pyrococcus furiosus | |
861 | - |
methyl beta-D-galactoside | release of methanol, pH 7.5, 80°C | Pyrococcus furiosus |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Pyrococcus furiosus | Q51723 | - |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
2-nitrophenyl beta-D-galactoside | - |
Pyrococcus furiosus | 2-nitrophenol + D-galactose | - |
r | |
lactose + H2O | - |
Pyrococcus furiosus | D-glucose + D-galactose | - |
r | |
methyl beta-D-galactoside | - |
Pyrococcus furiosus | methanol + D-galactose | - |
r | |
additional information | enzyme additionally catalyzes transglycosylation reactions, making new beta(1->3) and beta(1->6) glycosidic bonds by intermolecular as well as intramolecular transfer reactions. The intramolecular galactosyl transfer of CelB yields beta-D-Galp-(1->6)-D-glucose and beta-D-Galp-(1->3)-D-glucose in a molar ratio of about 1 : 2. Galactosyl transfer from CelB to D-glucose occurs with partitioning ratios, kNu /kwater, which are 170 times those for the reactions of the galactosylated enzyme with 2-propanol. Therefore, the binding interactions with nucleophiles contribute chiefly to formation of new beta-glycosides during lactose conversion. Likewise, noncovalent interactions with the glucose leaving group govern the catalytic efficiencies for the hydrolysis of lactose | Pyrococcus furiosus | ? | - |
? |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
8.3 | - |
methyl beta-D-galactoside | release of methanol, pH 7.5, 80°C | Pyrococcus furiosus | |
3800 | - |
lactose | release of D-glucose, pH 7.5, 80°C | Pyrococcus furiosus | |
10000 | - |
2-nitrophenyl beta-D-galactoside | release of 2-nitrophenol, pH 7.5, 80°C | Pyrococcus furiosus |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.01 | - |
methyl beta-D-galactoside | release of methanol, pH 7.5, 80°C | Pyrococcus furiosus | |
20.4 | - |
lactose | release of D-glucose, pH 7.5, 80°C | Pyrococcus furiosus | |
1900 | - |
2-nitrophenyl beta-D-galactoside | release of 2-nitrophenol, pH 7.5, 80°C | Pyrococcus furiosus |